Process for treating textiles used in aeronautics and aviation, and the aeroplane-framework produced thereby.



TED STATES PATENT OFFICE.

EMMANUEL AUGUSTIN JOSEPH DESGAMPS, OF RAIZEUX, FRANCE, ASSIGNOR TO SOGIETE LEDUC, HEITZ ET CIE., OF BAIZEUX, FRANCE.

PROCESS FOR TREATING TEXTILES USED IN AERONAUTICS AND AVIATION,'AND THE AEROPLANE-FRAMEWORK PRODUCED THEREBY.

No Drawing.

To all whom it may concern Be it known that I, EMMANUEL AUGUSTIN J osnrn DnsoAMrs, a citizen of the Republic of France, residing in Raizeux, Seine-et- Oise, France, have invented certain new and useful Improvements in'Processes for Treating Textiles Used in Aeronautics and Aviation, and the Aeroplane-Framework Produced Thereby, of which the following is a specification.

Varnish composed of solutions of cellulose-esters has been found to produce an increase of the tensile strength of tissues, When applied thereto. The present invention is a process based on the application of this quality of these special varnishes, and it consists in treating textiles of cotton, linen, etc., so as to produce a shrinking thereof and at the same time render them impermeable to water and gas, without appreciably altering their elasticity. Such tissues-are often used for the gasbags of dirigibles, and are quite impermeable interiorly to the gas, exteriorly to water; the process is also well suited tostretch and smooth the fabric forming the surfaces of aeroplanes. These surfaces become then perfectly rigid and smooth, and have a much lessened resistance to advancement in air.

The liquid varnish, a solution of celluloseesters, penetrates readily between the capillar cavities formed by the textile fibers, envelops the nearly microscopical fibers emerging at the surface of'the textile, fills up all the intervals between the fibers, connects all the threads and makes a perfect joint between them and the small emerging fibers. After the solvent has evaporated, and the varnish is' dry, the textile becomes perfectly impermeable, as all the intervals between threads have been diminished by the shrinking, and filled up with cellulose-ester, which is, like all these substances, more or less elastic. These textiles so treated can resist atmospherical influences, such as moisture, and even rain. As they are water tight and impermeable to gases, they are quite specially adapted for constructing dirigibles, as said above, and have the advantage of making a lighter tissue, which is a consideration of importance in aeronautics.

As to aeroplane wings, the invention consists in stretching and smoothing these.

Specification of Letters Patent.

Patented Oct. 19, 19115.

Application filed October 6, 1911. Serial No. 653,253.

Considering the method of constructing an aeroplane wing, that is, by application of textile on a ribbed frame-work, it is easily seen, that a supplementary tension caused by the application of this varnish is of great importance. -The shrinking is the same as above described, and it causes a tension unknown till now, which assures to the whole wing a rigidity, a solidity, and a regularity and smoothness which are of a very great value, as they fulfil the conditions, of a perfect aeroplane-Wing. The rigidity an smoothness of the wing are causes of a lessening of resistance to advancement in air. 1 7

It is by completely coating the threads and the textile fibers with these celluloseester-varnishes, that the smoothing is obtained,as the little threads and hairy fibers emerging from the surface of an untreated textile are what increase the viscosity of the air on the surfaces and form a resistance to the advancement of the aeroplane in the air. The varnish causes the complete disa )pearance of these little filaments, they being united to the surface of the varnish, so that after drying of the varnish, they are embedded in the solid coating. If they should cause an irregularity of the surface, a little rubbing with an emery paper will equalize the surface, and the'application of a second, or a thirdcoating of "arnish will produce a high degree of smoothness. These coatings .unite one to the other, and therefore their application is easy, and they furthermore form one mass with the textile, being solidly anchored in it by the filaments and by the part of the coating which penetrated into the interstices.

A similar result is never'obtained by other varnishes, as these are not neutral, have oxidation products reacting with the fibers, and, because of their Viscosity, their penetration between the threads is less; other varnishes again leave unelastic coatings they also swell'the little fibers and filaments so that they emerge more than before, and form a greater resistance to air.

If the effect of stretching of the textiles already on the ribs forming an aeroplane wing is to be obtained, the varnish is applied with a brush; but if the effect of smoothing only is desired, the textile can be passed between the rolls of a varnishing calender, these rolls giving also a smooth surface by pressing down the little filaments in the mass of the varnish. These varnishes of cellulose esters, for stretching and smoothing and impermeabilizing textiles for aviation and aeronautical purposes are ordinarily composed of a solution of cellulose acetate in acetone, or tetrachlorure of ethane. If other liquids are joined to diminish the viscosity, it is good if these have about the same boiling point as the principal solvent, in order not to have some volatile residues entrapped in the coating: It is good to use for instance equal parts by weight of pyridin and tetrachlorure of ethane, or of ace-.

tone and methylic alcohol, and in preparing a 10% solution of cellulose acetate with them. One can also make a 33% solution of cellulose-esters in acetone, and dilute this with a mixture of benzene and alcohol.

The tensile strength of an aeroplane wing is remarkably increased, and this increase is permanent, and does not change after much use of the aeroplane.

Claims:

1. The process of applying a textile fabric to a framework or body consisting in fastening the fabric to the framework or body, impregnating the fabric with a liquid celluloseester varnish, and evaporating the solvent of the varnish, whereby said fabric is rendered impervious and stretched tautly.'

2. The process of applying a textile fabric to a framework or body consisting in fastening the fabric to the framework or body, impregnatin the fabric with a cellulose-ester varnish dissolved in solvents having similar boiling points and vapor tensions, and evaporating the solvents of the varnish, whereby said fabric is rendered impervious and stretched tautly.

3. The process of applying textile fabrics to the framework of aeroplanes, consisting vent from said varnish, whereby said fabric is stretched tightly upon the framework, the interstices of said fabric filled, and the fibers, including the superficial fibers are closely cemented together, so that the surface of the fabric presents a smooth, hard, impervious surface to the air.

4. An aeroplane, framework having a textile fabric fixed thereto, said textile fabric being impregnated with a cellulose ester, said cellulose-ester causing a shrinking of the fabric and thereby imparting a contractile stress through the body of the fabric to the framework, whereby the fabric is tautly' stretched upon said framework, said cellulose-ester also augmenting the tensile strength of said fabric whereby said fabric possesses greater resistance to stresses tending to flex or elongate the same.

5. An'aeroplane, framework having a textile fabric-fixed under tension thereto, said textile fabric being impregnated with a cellulose-ester, said cellulose-ester causing a shrinking of the fabric and thereby imparting a contractile stress through the body of the fabric to the framework, whereby a supplementary tension is applied to said fabric and the fabric is tautly stretched uponsaid framework, said cellulose ester also augmenting the tensile strength of said fabric whereby said fabric possesses greater resistance to stresses tending to flex or elongate the same.

In witness whereof, I havehereunto signed my name in the presence of two subscribing witnesses.

EMMANUEL AUGUSTIN JOSEPH DESCAMPS.

Witnesses:

H. C. COKE, RENE BARDY. 

